bendns' repos / lower
desugars operator overloading
Diffstat (limited to 'src/lib.rs')
-rw-r--r--src/lib.rs65
1 files changed, 30 insertions, 35 deletions
diff --git a/src/lib.rs b/src/lib.rs
index fbd0e7f..174994b 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -389,48 +389,43 @@ fn walk_item<T: Sub>(x: Item) -> TokenStream {
}
}
-/// Lower math to method calls.
-/// ```
-/// # use std::ops::*;
-/// let [a, b, c] = [5i32, 6, 7];
-/// assert_eq!(lower_macros::math! { a * *&b + -c }, a * *&b + -c);
-/// // expands to
-/// // a.mul((&b).deref()).add(c.neg())
-/// ```
+macro_rules! walk {
+ ($input:ident,$t:ty) => {
+ match parse::<Expr>($input.clone())
+ .map(walk::<$t>)
+ .map_err(|x| x.to_compile_error().into_token_stream())
+ {
+ Ok(x) => x,
+ Err(e) => parse::<Stmt>($input).map(walk_stmt::<$t>).unwrap_or(e),
+ }
+ .into()
+ };
+}
+
#[proc_macro]
pub fn math(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
- match parse::<Expr>(input.clone())
- .map(walk::<Basic>)
- .map_err(|x| x.to_compile_error().into_token_stream())
- {
- Ok(x) => x,
- Err(e) => parse::<Stmt>(input).map(walk_stmt::<Basic>).unwrap_or(e),
- }
- .into()
+ walk!(input, Basic)
}
#[proc_macro]
-pub fn algebraic(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
- match parse::<Expr>(input.clone())
- .map(walk::<Algebraic>)
- .map_err(|x| x.to_compile_error().into_token_stream())
- {
- Ok(x) => x,
- Err(e) => parse::<Stmt>(input)
- .map(walk_stmt::<Algebraic>)
- .unwrap_or(e),
- }
- .into()
+pub fn fast(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
+ walk!(input, Fast)
}
#[proc_macro]
-pub fn fast(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
- match parse::<Expr>(input.clone())
- .map(walk::<Fast>)
- .map_err(|x| x.to_compile_error().into_token_stream())
- {
- Ok(x) => x,
- Err(e) => parse::<Stmt>(input).map(walk_stmt::<Fast>).unwrap_or(e),
+pub fn algebraic(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
+ walk!(input, Algebraic)
+}
+
+#[proc_macro_attribute]
+pub fn apply(
+ args: proc_macro::TokenStream,
+ input: proc_macro::TokenStream,
+) -> proc_macro::TokenStream {
+ match &*args.to_string() {
+ "basic" | "" => math(input),
+ "fast" => fast(input),
+ "algebraic" => algebraic(input),
+ _ => quote! { compile_error!("type must be {fast, basic, algebraic}") }.into(),
}
- .into()
}